Centrifugal impact pulverizing apparatus.



D. 0. MARKS.

GBNTRIFUGAL IMPACT PULVBRIZING APPARATUS.

APPLICATION FILED DEC. 17, 1907. 994,596. Patented June 6, 1911.

2 SHEETS-SHEET 2.

D. 0. MARKS.

GENTRIFUGAL IMPACT PULVERIZING APPARATUS.

APPLIUATIQN FILED DBO.17, 1907.

994,596 Patented June 6,1911.

2 SHEETS-SHEET 1.

fronn 05am EE r ATENT OFFICE.

DONN OTTO MARKS, 0F DENVER, COLORADO, ASSIGNOR TO THE MARKS PULVERIZING,MINING AND MILLING MACHINERY 00., OF DENVER, COLORADO, A CORPORATION OFCOLORADO;

CENTRIFUGAL IMPACT .PULVERIZING APPARATUS.

Specification of Letters Patent.

Application filed December 17, 1907.

Patented June 6, 1911.

Serial No. 406,953.

To all whom it may concern:

Be it known that I, DONN O'r'ro MARKS, a citizen of the United States,formerly residing at Los Angeles, California, now a resident of the cityand county of Denver and State of Colorado, have invented a new anduseful Centrifugal Impact Pulverizing Apparatus, of which the followingis a specification.

This invention relates to an apparatus designed for pulverizingsubstances of many kinds by impact of the same upon a corrugated wallagainst which said substances are impelled by centrifugal force from arotary impeller; and relates to the further treatment of such substancesby centrifugal force for the purpose of delivering the product inassorted sizes for subsequent treatment. I

The apparatus is designed for alternative operation upon either wet ordry materials as occasion may arise, without any change in theconstruction or adjustment of the machine, and to perform the operation,without inconvenience or injury from dust, upon dry substances capableof being reduced to impalpable powder; and also to produce sloppy.

material like'the pulp from stamp mills.

An object of, the invention is to avoid excessive wear and to readilyreplace or compensate for any wear that may occur in any of the partsoft-he apparatus.

Other objects are effectiveness, cheapness, simplicity, compactness,convenience of operation, and avoidance of air friction and resistancewithin the pulverizin chamber. Theaccompanying drawings il ustrate' theinvention.

Figure 1 is a plan view of ap aratus embodying this invention, portionsbeing broken away to expose interior construction. Fig. 2 is a sideelevation of the apparatus omitting the spout through which the coarserproduct may discharge from the separator, and also the elevator and beltwhich impeller is broken away to expose parts that would otherwise beconcealed. Fig. 4 is a vertical, sectional elevation of the apparatus.Fig. 5 is an enlarged fragmental detail of the mounting for the rotaryimpeller. Fig. 6 is a fragmental, sectional detail on line m w, Fig. 4.Fig. 7 is a sectional elevation on line 02, looking into the mouth ofthe impellenchamber. The wall of said chamber is broken to eX- poseinside parts. Fig. 8 is a fragmental view to show the mouths of theseparator. Fig. 9 is an enlarged sectional detail of the lower end ofthe separator. Fi 10 is an enlarged perspective detail to illustrate animpeller-shoe in place on oneof the radial walls or blocks, a fragmentof the impeller being shown.

1 designates in a general way a rotary its upper end with a threadedarbor 7 onto which is screwed the plate 2 and hub 5. A portion 8 of saidshaft immediately below the arbor 7 tapers downwardly for adjust ment inthe upper shaft-bearing 9 which is provided with a cylindrical bore 10that is filled with babbittlng 11 around said tapering portion to form abushin therefor. The portion of the. shaft below t e tapering portion 8is cylindrical, and its lower end is provided with a screw-threadedsocket 12, to receive a screw-threaded stem 13 of a hardened steel foot14, which forms the lower end of the shaft 6 and is provided withasemispherical cavity 15 to rest on an antifriction hardened steel ball16, which is carried by an adjustable hardened steel plate 17 arrangedto move vertically in the bearing-way18, in which it is adjustably heldby a screw 19 fixed by a jam-nut 20.

21 is babbitting for the lower bearing 22 through the bottom of whichbearing the screw 19 screws.

23 is a pulley fixed on shaft 6 to rotate the same.

(1 is. a belt to drive the pulley. I

24, 25- designate upper and lower dustexcluding washers preferably madeof felt and tightly fitting the shaft 6 above the top and bottombearings therefor. These washers are held compressed by resilient means,as the springs 26, 27 ,operable by the shaft 6, the spring 26 beingcompressed by a cap 28 fixed to'said shaft and inclosing and movany wearthat may occur in the upper bearing where wear .is most liable *tooccur, and where it causes-the greatest derangement when it does occur.

30 designates a chamber with corrugated walls 31 within which theimpeller 1 rotates.

Said chamber is formed inside the upper body of a frame 32 which carriesthe upper and lower bearings 9 and 22, and .is of considerable depthbelow the corrugated walls 31 which are preferably formed in removablesegments 33 and rest upon a. ledge 34 in said frame. The floor 35 of thechamber slants from one side of thechamber to the outlet mouth 36 whichis of considerable width so as to allow the material crushed byimpact-with the wall 30 to pass out freely below said wall.

37 is a hopper cast in a single piece with the top plate 38 of the frame32. The lower edge of the hopper 37 extends into the unobstructedannular opening between the up per end of the post 5 and the inner edgeof the annular plate 4 as the post 5 is adjusted up and down. I

39 is a chute to,discharge into said hopper.

40 is a conduit leading from the horizontally-distended discharge mouth36 of the chamber to the cylindrical upper portion 41 of afrusto-conical screening and separating device 42. This conduit 40 isgradually reduced in its horizontal dimensions and distended initsvertical dimensions toward the outlet mouth 43 thereof, whichdischarges 3 into the interior of the separator 42 so that thepulverizedmaterial will enter the separator tangentially. Said separator 42comprises an exterior frusto-conical imperforate shell 44 having aflaringv annular outlet mouth 45 at the bottom. a

46 is a foraminate screen-like inner wall within the imperforate shell44, the same terminating in a flaring imperforate portion 47 having a.downwardly-opening tubular outlet 48 to discharge from the bottom of theinner screen-chamber any material that does not pass through the screen.

49 is a pipe having an intake mouth 50 "inside the screen-chamber 51below the level of the mouth 43 of the conduit 40. Said pipe extendsupward from said mouth 50 and opens into the chute 39. Said chute isprovided -with open-topped feed entries or inlets 52 which communicatethrough valved ports 53 with the interior of the chute 39. Said portsare yieldingly closed by swinging doors 54.

In practice, the impeller is driven in a determined direction, asindicated by the curvedarrow in Fig. 3, and the forward upright faces 3of the impeller are arranged in a plane radial from the axis of theimpeller, so that when any material enters the annular spacein therotating impeller be tween the annular plate 4 and the hub 5,

the motion imparted thereto by the hub and base plate will cause thematerial to flow outward by centrifugal force until caught by animpeller face 3, whereupon the material is instantly put into motion ata high speed and therefore flies off from the im-' peller at'a tangent,strikes the corrugated wall, and is thereby pulverized. At the sametime, the impeller faces -3 operate in the nature of a blower sothat astrong blast of air is thrown from the impeller and passes outward anddownward underneath the corrugated wall and out the mouth 36 through theconduit 40 and into the screenchamber- 51 of the separator at thecylindrical top thereof.

By reason of the tangential arrangement of the mouth 43, quite clearlyshown in Fig. 1, the material passing from the conduit 40 is directed ina circular path around the cylindrical portion a of the screen46 andtends to fly outward.- At the same time the force of gravity draws theparticles downward onto the conical portion 1) of the screen-wall 46around which the material willpassin a spiral course as it passesdownward to the.

outlet-tube 48. By this construction and arrangement the material whichenters the screen-chamber 51' is constantly acted upon by forces whichtend to cause such material to pass through the screen into theouterchamber 0 between the screen 46 and the shell 44. 'When thematerial passes into the open space '0 itis guided downward in wardly bythe outer shell 44 until it finds egress through the annular mouth 4:5.The material that is too coarse to pass through the screen, flows downand out at the tube 48. In this way the finer material will bedischarged at one place and the coarser material at another.

55 designates av spout leading from the tube 48' to carry the coarsermaterial out through the path of the finer material which may flow in anannular stream out of the mouth 45. v

e in Fig. 1 designates the conveying tube of any well-known form ofelevator for. returning the over-size material from spout 55 to one ofthe feed entries 52.

56 is a removable cover for the chamber of the separator. By removingthe pipe 49 and the cover 56, the screen 46 with its outlet tube 48 maybe removed.

In practical operation the impeller will be rotated at a high speed,say, 2500 revolutions more or less per minute, thereby insuring highefliciency as to the comminuting action, andalso great capacity forspeedily handling large quantities of material.

The material to be pulverized or comminuted may be fed in at thehopper-like openings 52 down the slanting floors of which it will passby gravity, forcing the swinging doors 53 inward, whereupon the materialwill flow into the chute 39 and hopper 37 and thence into the openingwithin the annular top-plate, and onto thehub and baseplate of theimpeller where it will artake of the motion of said impeller and wilthereby be driven tangentially 'in a horizontal course against thecorrugated wall 31 from which it will pass downward and outward throughthe peripheral outlet 36, being impelled both by the force of gravityand by the air blast from the impeller, and thence at a very hi h rateof speed throu h the vertical slot-llke outlet 43 tangential y into theseparator where it whirls around and around, circling downward in aspiral course, the finer portions passing through the screen 46 anddischarging at the annular mouth 45,

while the coarser material passes down to and through the tube 48 andout through the s out 55, and thence to the elevator yea and t en to thefeed-entry 52. During. this operation the dust-laden air passes up outthrough the pipe 49 and down into the impeller-head by which it is againimpelled as before, thus effecting a continuous circulation of airwithin the machine without escape of the dust-laden air exteriorly. Thedust contained in the air thus returned to the. impeller may now findits way throu h ,the screen 46 and thence out through t e mouth 45. Thedownwardly-tapering separator causes the fine and coarse material toseparately discharge within a small radius,

so that the same may be readily directed where required.

Owing to the high speed of rotation of the impellersshaft it is imortant that the upper bearing thereof sha 1 not at any time be loose.When the impeller is first installed the adjusting screw '19 is fullyscrewed up, thus holding the impeller head at its upper limit. Thechamberin which ,said head rotates isof greater depth than the head,thus allowing the operator to screw the adjustin screw downward to lowerthe impeller-sha t from time to time to compensate for wear and to bringthe tapering portion 8 to'seat snugly in the babbitting.

The tendency to wear loose is. greatest at the upper bearing, andtherefore the lower bearing and the lower journal pf the impeller-shaftare made cylindricalfi thus to allow the shaft to move freel up and downtherein. When the shaft as reached its lowest limit vof adjustment thescrew may be screwed up again, thus bringing the shaft to its highestposition, whereu on the bearings may be rebabbitted. Bus ings of any"sultable material may be substituted for the babbitting 10 and 21 whendesired.

The base-plate 2 of the impeller may be provided with blocks 57 to whichthe annular top-plate 4 may be fastened by screws or bolts 58. On theseblocks may be mounted reversible U-shaped shoes 59 havingsemicylindrical heels 60 at the inner margin of the top-plate 4, thepurpose being to make the impeller faces easily renewable. The shoes maybe inserted into and withdrawn from the hollow impeller and applied tothe blocks through the annular opening inside the top-plate 4. a

The central post tapers upwardly from the base plate to ap roz cimate ythe level of thetop plate, and t e inner ends of the impeller facesterminate approximately at the inner circular rim of the top plate, sothat an annular unobstructed open space'is provided around the post 5 sothat material which may fall on or strike the post may be iven a rotaryimpulse thereby, which may e imparted to much of the material fed intothe openi'n in the top plate before the same reaches ,tfie base-plate,and in consequence, the materialis started to rotate before being caughtby the im eller faces and before reaching the level 0 thebase-plate.This tends to cause an even distribution ofthe material from top tobottom of the vertical impeller faces'a-nd the ortion of the impact wallthat receives th ischarge from the impeller. t E It is to be understoodthat by reason of the high speed at which the impeller faces revolve,the material which reaches said faces is discharged therefrom at a speedmany. times greater than'that at which the. force of gravity underordinary circumstances will feed material to the impeller. That is tosay, in the apparatus shown in the drawings, the material may, under theforce of. gravity, travel downward at the rate of about 16 feet persecond, 'which is' far less than the speed at which the material will bethrown outward by the action of the impeller. Consequently, there isnever any accumulation of material in the impeller.

The impeller including the base plate, the hollow post, the top plate,and vertical blocks carrying the faces 3, may be cast in a single piece,as indicated in Fig. 4; or, if desired, the top plate may be secured tothe bottom plate by bolts or screws 0? in said blocks, as indicated inFig. 10.

' What I claim is 1. In a centrifugal impact pulverizer, a

frame provided with a chamber having .a

' central inlet at its top and having a. periphinlet into said chamberand having a pe- 'ripheral outlet at thebottom of the chamber, anannular impact wall formed in the chamber above said outlet and belowthe level of the inlet; a vertical shaft provided with a downwardlytapering portion in the upperrbearing, and with a cylindrical portion inthe lower bearing, babbitting in the upper bearing to fit sald taperportion, a rotary impeller on said shaft in said chamber and spacedapart from said wall, and adjustable means for lowering said shaft todifferent heights to take up the wear in said upper bearing, said impactwall being adapted and arranged to receive the discharge from said headat various heights of adjustment.

In testimony whereof, I'have hereunto set my hand at Denver, Colorado,this seventh day of December, 1907.

LYNN S. ATKINSON, A. RAND.

